Free fatty acid physical properties

Both acid oil and the free fatty acids obtained in the physical refining may be incorporated in the manufacture of soap. In view of its high linoleic acid content (in particular when originating in the refining of regular sunflower oil), soapstock does not make a fatty material of good properties for the manufacture of toilet soap. To this end, it is blended in relatively low proportions with other more appropriate fatty materials. It is used in cattle producer countries also producing sunflower oil as a means to reduce the titer of beef tallow or of the beef tallow/coconut oil blend. 

The simplest and most efficient technique for obtaining 0)3 PUFA concentrates in the form of free fatty acids is urea complexation. This technique is well established for elimination of saturated and monounsaturated fatty acids (70). In this method, the saturated and monounsaturated fatty acids can easily complex with urea after hydrolysis of TAG with aUcaline, and crystallize out on cooling and may subsequently be removed by filtration (70). This method is favored by many researchers because complexation depends on the configuration of the fatty acid moieties because of the presence of multiple double bonds, rather than of pure physical properties such as melting point or solubility (10). 

Table III gives the physical and chemical properties of the M. oleifera oil. Some of the properties of the oil depend on the extraction medium. The M oleifera oil is liquid at room temperature and pale-yellow in colour. Electronic nose analysis shows that it has a flavor similar to that of peanut oil. The melting point estimated by differential scanning calorimetry is 19°C (15). The chemical properties of the oil depicted in Table III below are amongst the most important properties that determines the present condition of the oil. Free fatty acid content is a valuable measure of oil quality. The iodine value is the measure of the degree of unsaturation of the oil. The unsaponifiable matter represents other lipid- associated substances like, sterols, fat soluble vitamins, hydrocarbons and pigments. The density, iodine value, viscosity, smoke point and the colour of Moringa oil depends on the method of extraction, while the refractive index does not. Varietal differences are significant in all physical characteristics apart from refractive index and density (2). The heating profile of the M. oleifera seed oil using the differential scanning calorimetry (DSC) conventional scan rate shows that there is one major peak B and, two small shoulder peaks A and C...

Palm oil physico-chemical properties allow it to be the most widely fractioned oil (Table 2). Fractioning involves physical or chemical refine applying high temperatures, desodorisation and deacidification of oil under vacuum, in both cases. Physical deacidification accurs at 250-270 C under vacuum up to 3-5 Torr, whereas chemical uses 220-240 °C. The high temperatures and vacuum are necessary to remove undesirable compounds as traces of metals, free fatty acids, oxidation and decomposition products. Nevertheless, those procedures also remove some tocopherols and tocotrienols, and all carotenoids presented in the oil [30, 31, 32, 33,34]. 

The kernel oil is obtained by expelling, usually followed by solvent extraction. The oil superficially resembles coconut oil in chemical and physical properties. The free fatty acid of the crude oil varies from 0.5 to 10%, plantation oils normally having the lowest values. The refined oil keeps well but has a tendency to form soapy rancid off-flavours under conditions in which microbial or lipolytic activity has not been controlled. 

Free Fatty Acid Soap bars are intrinsically alkaline in nature on account of the physical properties of soap in water and the process utilized in its manufacture, which yields base... 

The physical properties of the fatty acid ethoxylates depend on the nature of the fatty acid and even more on ethylene oxide content. As the latter increases, consistencies of the products change from free-flowing Hquids to slurries to firm waxes (qv). At the same time, odor, which is characteristic of the fatty acid, decreases in intensity. Odor and color stabiUty are important commercial properties, particularly in textile appHcations. Oleic acid esters, though possessing good functional properties, cannot be used because they tend to yellow on exposure to heat and air. 

The finding that water-soluble flavonoids could exert their beneficial properties at the hydrophobic portion of the membrane was also observed in in vivo studies and in cells in culture. For example, erythrocytes obtained from animals fed a flavanol- and procyanidin-rich meal showed reduced susceptibility to free-radical-mediated hemolysis [Zhu et al., 2002]. Consistently, we demonstrated that procyanidin hexamers, which interact with membranes but would not be internalized, protected Caco-2 cells from AMVN- and bile-induced oxidation [Erlejman et al., 2006]. When liposomes were preincubated with a series of flavonoids with diverse hydrophobicity, not only hydrophobic flavonoids prevented AMVN-mediated lipid oxidation but also the more hydrophilic ones [Erlejman et al., 2004]. Similarly to what was previously found in liposomes, the protective effects of flavonoids against AMVN-supported oxidation was strongly associated with their capacity to prevent membrane disruption by detergents, supporting the hypothesis of a physical protection of membranes by preventing oxidants to reach fatty acids. 

At this point, it is useful to examine the effect of uncertainty in data by sensitivity analysis. Some physical properties are essential for design, such as for example the vapor pressure of the fatty ester, VLE for binaries involving the lauric acid, alcohol and water, as well as the Gibbs free energy of formation of the fatty ester. 

Commonly, the fatty acids in food lipids are exposed to heat during oil processing and food manufacture. Once peroxides are formed, they can decompose and generate free radicals, and the rate of peroxide decomposition increases with temperature. Such reactions are of extreme importance to both consumers and processors, because of their flavor significance, and under frying conditions they can affect the physical, nutritional, and toxological properties of the fried food. 

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